999 resultados para 155-942


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Dopamine (DA) is a neuromodulator in the brainstem involved with the generation and modulation of the autonomic and respiratory activities. Here we evaluated the effect of microinjection of DA intracistema magna (icm) or into the caudal nucleus tractus solitarii (cNTS) on the baseline cardiovascular and respiratory parameters and on the cardiovascular and respiratory responses to chemoreflex activation in awake rats. Guide cannulas were implanted in cisterna magna or cNTS and femoral artery and vein were catheterized. Respiratory frequency (f(R)) was measured by whole-body plethysmography. Chemoreflex was activated with KCN (iv) before and after microinjection of DA icm or into the cNTS bilaterally while mean arterial pressure (MAP), heart rate (HR) and f(R) were recorded. Microinjection of DA icm (n = 13), but not into the cNTS (n = 8) produced a significant decrease in baseline MAP (-15 +/- 1 vs 1 +/- 1 mm Hg) and HR (-55 +/- 11 vs -11 +/- 17 bpm) in relation to control (saline with ascorbic acid, n = 9) but no significant changes in baseline f(R). Microinjection of DA icm or into the cNTS produced no significant changes in the pressor, bradycardic and tachypneic responses to chemoreflex activation. These data show that a) DA icm affects baseline cardiovascular regulation, but not baseline f(R) and autonomic and respiratory components of chemoreflex and b) DA into the cNTS does not affect either the autonomic activity to the cardiovascular system or the autonomic and respiratory responses of chemoreflex activation. (C) 2010 Elsevier B.V. All rights reserved.

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In vitro, nitric oxide (NO) inhibits the firing rate of magnocellular neurosecretory cells (MNCs) of hypothalamic supraoptic and paraventricular nuclei and this effect has been attributed to GABAergic activation. However, little is known about the direct effects of NO in MNCs. We used the patch-clamp technique to verify the effect Of L-arginine, a precursor for NO synthesis, and N-omega-nitro-L-arginine methyl ester hydrochloride (L-NAME), an inhibitor of NOS, on spontaneous electrical activity of MNCs after glutamatergic and GABAergic blockade in Wistar rat brain slices. 6-Cyano-7-nitroquinoxaline-2,3-dione (CNQX) (10 mu M) and DL-2-amino-5-phosphonovaleric acid (DL-AP5) (30 mu M) were used to block postsynaptic glutamatergic currents, and picrotoxin (30 mu M) and saclofen (30 mu M) to block ionotropic and metabotropic postsynaptic GABAergic currents. Under these conditions, 500 mu M L-arginine decreased the firing rate from 3.7 +/- 0.6 Hz to 1.3 +/- 0.3 Hz. Conversely, 100 mu M L-NAME increased the firing rate from 3.0 +/- 0.3 Hz to 5.8 +/- 0.4 Hz. All points histogram analysis showed changes in resting potential from -58.1 +/- 0.8 mV to -62.2 +/- 1.1 mV in the presence of L-arginine and from -59.8 +/- 0.7 mV to -56.9 +/- 0.8 mV by L-NAME. Despite the nitrergic modulator effect on firing rate, some MNCs had no significant changes in their resting potential. In those neurons, hyperpolarizing after-potential (HAP) amplitude increased from 12.4 +/- 1.2 mV to 16.8 +/- 0.7 mV by L-arginine, but without significant changes by L-NAME treatment. To our knowledge, this is the first demonstration that NO can inhibit MNCs independent of GABAergic inputs. Further, our results point to HAP as a potential site for nitrergic modulation. (C) 2008 IBRO. Published by Elsevier Ltd. All rights reserved.

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Purpose To determine the relationship between ocular hypertension and glaucoma in patients with Graves` orbitopathy. Methods A total of 107 patients with a diagnosis of Graves` orbitopathy, followed at the Oculoplasty sector of the University Hospital, Medical School of Ribeirao Preto, were evaluated by applanation tonometry, computed visual campimetry (Humphrey 30-2, Full Threshold) and analysis and photographic documentation of the optic nerve. The patients considered to have the suspicion of glaucoma were re-evaluated 1 year later for diagnostic confirmation or exclusion. Results A 3.74% prevalence of ocular hypertension (four patients) and a 2.8% prevalence of glaucoma (three patients) was observed. When considering only patients older than 40 years, the prevalence of ocular hypertension was 5.4% (four patients) and the prevalence of glaucoma was 4.76% (three patients). Conclusion The present study did not reveal a statistically significant difference in the prevalence of ocular hypertension or glaucoma between patients with Graves` orbitopathy and the general population.

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The HLA-G gene is predominantly expressed at the maternal-fetal interface. It has been associated with maternal-fetal tolerance and in the inhibition of cytotoxic T lymphocyte and natural killer cytolytic functions. At least two variations in the 3` untranslated region (UTR) of HLA-G locus are associated with HLA-G expression levels, the 14-bp deletion/insertion polymorphism and the +3142 single-nucleotide polymorphism (SNP). However, this region has not been completely characterized yet. The variability of the 3`UTR of HLA-G gene and its haplotype structure were characterized in 155 individuals from Brazil, as well as HLA-G alleles associated with each of the 3`UTR haplotype. The following eight variation sites were detected: the 14-bp polymorphism and SNPs at the positions +3003T/C, +3010C/G, +3027A/C, +3035C/T, +3142G/C, +3187A/G and +3196C/G. Similarly, 11 different 3`UTR haplotypes were identified and several HLA-G alleles presented only one 3`UTR haplotype. In addition, a high linkage disequilibrium among the variation sites was detected, especially among the 14-bp insertion and the alleles +3142G and +3187A, all previously associated with low mRNA availability, demonstrating that their effects are not independent. The detailed analyses of 3`UTR of the HLA-G locus may shed some light into mechanisms underlying the regulation of HLA-G expression. Genes and Immunity (2010) 11, 134-141; doi: 10.1038/gene.2009.74; published online 1 October 2009

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Methionine-choline-deficient diet represents a model for the study of the pathogenesis of steatohepatitis. Male rats were divided into three groups, the first group receiving a control diet and the other two groups receiving a methionine-choline-deficient diet for 1 month (MCD1) and for 2 months (MCD2), respectively. The livers of the animals were collected for the determination of vitamin E, thiobarbituric acid reactive substances (TBARS), GSH concentration, DNA damages, and for histopathological evaluation. The hepatic TBARS and GSH content was higher (P < 0.05) in the groups receiving the experimental diet (MCD1 and MCD2) compared to control diet, and hepatic vitamin E concentration differed (P < 0.05) between the MCD1 and MCD2 groups, with the MCD2 group presenting a lower concentration. Damage to hepatocyte DNA was greater (P < 0.05) in the MCD2 group (262.80 DNA injuries/100 hepatocytes) compared to MCD1 (136.4 DNA injuries/100 hepatocytes) and control diet (115.83 DNA injuries/100 hepatocytes). Liver histopathological evaluation showed that steatosis, present in experimental groups was micro- and macro-vesicular and concentrated around the centrolobular vein, zone 3, with preservation of the portal space. The inflammatory infiltrate was predominantly periductal and the steatosis and inflammatory infiltrate was similar in the MCD1 and MCD2 groups, although the presence of Mallory bodies was greater in the MCD2 group. The study describes the contribution of a methionine-choline-deficient diet to the progression of steatosis, lipid peroxidation and hepatic DNA damage in rats, serving as a point of reflection about the role of these nutrients in the western diet and the elevated non-alcoholic steatohepatitis rates in humans.

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The present study was performed in an area endemic for Brazilian spotted fever (BSF) in Juiz de Fora, state of Minas Gerais, Brazil, during the years 2007 and 2008, when fatal cases of BSF (caused by Rickettsia rickettsii) were reported. Adult ticks (Acari: Ixodidae) identified as Rhipicephalus sanguineus (Latreille) and Amblyomma cajennense (Fabricius) were collected from dogs and horses, respectively, and tested by polymerase chain reaction (PCR). Overall, 13.1% of the Rh. sanguineus ticks and none of the A. cajennense were found to be infected with R. rickettsii. Two isolates of R. rickettsii were successfully established in Vero cell culture from two Rh. sanguineus ticks. An indirect immunofluorescence assay (IFA) using R. rickettsii antigens detected blood serological reaction to R. rickettsii in 67.9% (53/78) of dogs and 41.0% (16/39) of horses living in the study area. Larval offspring from two Rh. sanguineus engorged females, naturally infected by R. rickettsii, were reared to adult stage in the laboratory. All active stages (larvae, nymphs, adults) remained 100% infected by R. rickettsii, which was efficiently transmitted to naive rabbits. Overall, the results of the present study indicate a potential risk for transmission of R. rickettsii to humans by Rh. sanguineus, an occurrence yet to be documented in Brazil.

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Rabies virus (RABV) isolates from two species of canids and three species of bats were analyzed by comparing the C-terminal region of the G gene and the G-L intergenic region of the virus genome. Intercluster identities for the genetic sequences of the isolates showed both regions to be poorly conserved. Phylogenetic trees were generated by the neighbor-joining and maximum parsimony methods, and the results were found to agree between the two methods for both regions. Putative amino acid sequences obtained from the G gene were also analyzed, and genetic markers were identified. Our results suggest that different genetic lineages of RABV are adapted to different animal species in Brazil.

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The aim of this study was to determine if Toxoplasma gondii are present in oysters (Crassostrea rhizophorae) and mussels (Mytella guyanensis) under natural conditions using a bioassay in mice and molecular detection methods. We first compared two standard protocols for DNA extraction, phenol-chloroform (PC) and guanidine-thiocyanate (GT), for both molluscs. A total of 300 oysters and 300 mussels were then acquired from the fish market in Santos city, Sao Paulo state, Brazil, between March and August of 2008 and divided into 60 groups of 5 oysters and 20 groups of 15 mussels. To isolate the parasite, five mice were orally inoculated with sieved tissue homogenates from each group of oysters or mussels. For molecular detection of T. gondii, DNA from mussels was extracted using the PC method and DNA from oysters was extracted using the GT method. A nested-PCR (Polymerase Chain Reaction) based on the amplification of a 155 bp fragment from the B1 gene of T. gondii was then performed. Eleven PCR-RFLP (Restriction Fragment Length Polymorphism) markers, SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, CS3 and Apico, were used to genotype positive samples. There was no isolation of the parasite by bioassay in mice. T. gondii was not detected in any of the groups of mussels by nested-PCR. DNA of T. gondii was apparently detected by nested-PCR in 2 groups of oysters (3.3%). Genotyping of these two positive samples was not successful. The results suggest that oysters of the species C. rhizophorae, the most common species from the coast of Sao Paulo, can filter and retain T. gondii oocysts from the marine environment. Ingestion of raw oysters as a potential transmission source of T. gondii to humans and marine mammals should be further investigated. (C) 2010 Elsevier B.V. All rights reserved.

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FAPESP (the Sao Paulo State research funding foundation)

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Pfaffia paniculata (Brazilian ginseng) roots and/or its extracts have shown anti-neoplastic, chemopreventive, and anti-angiogenic properties. The aim of this work was to investigate the chemopreventive mechanisms of this root in Mice Submitted to the infant model of hepatocarcinogenesis, evaluating the effects oil cellular proliferation, apoptosis. and intercellular communication. Fifteen-day-old BALB/c male mice were given, i.p., 10 mu g/g of the carcinogen N-nitrosodiethylamine (DEN). Animals were separated into three groups at weaning and were given different concentrations of powdered P. paniculata root (0%, 2%, or 10%) added to commercial food for 27 weeks. Control group (CT) was not exposed to the carcinogen and was given ration without the root. After euthanasia, the animals` liver and body weight were measured. Liver fragments were sampled to Study intercellular communication, molecular biology, and histopathological analysis. Cellular proliferation was evaluated by immunohistochemistry for PCNA, apoptosis was evaluated by apoptotic bodies count and alkaline cornet technique, and inter-cellular communication by diffusion of lucifer yellow dye, immunofluorescence, western blot and real-time PCR for connexins 26 and 32. Chronic treatment with powdered P. paniculata root reduced cellular proliferation and increased apoptosis in the 2%, group. Animals in the 10% group had an increase in apoptosis with chronic inflammatory process. Intercellular communication showed no alterations in any of the groups analyzed. These results Indicate that chemopreventive effects of P. paniculata are related to the control of cellular proliferation and apoptosis, but not to cell communication and/or connexin expression, and are directly Influenced by the root concentration. (C) 2009 Elsevier GmbH. All rights reserved.

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This Study reports a case of parasitism by the giant kidney worm, Dioctophyma renale, diagnosed in the right kidney of a domestic (log An adult female German Shepherd was attended with clinical history of prostration and hyporexia. The hemogram showed changes compatible with an inflammatory process, for that reason, an abdominal ultrasound was requested. Ultrasound image suggested the presence of D renale in the right kidney The diagnosis was confirmed after urinalysis due to the presence of dioclophymas ova in the urinary sediment. Surgical treatment was made and the animal had an excellent recovery after the nephrectomy was performed Generally. in almost all cases, parasitism by D renale in domestic dogs is a necropsy finding, nevertheless imaging techniques as sonography and laboratorial exams as urinalysis have been proven to be important tools to achieve diagnosis. The purpose of this study is to report a case of parasitism by D renale where diagnosis and treatment were made in time to allow the patient`s recovery (C) 2009 Elsevier B V All rights reserved.

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This study was conducted to determine the effect of pre-exposure of oocytes to Ricinus communis (RCA-1) lectin and osteopontin (OPN) in uterine tube fluid (UTF) on in vitro sperm-egg binding and fertilization. In vitro-matured bovine oocytes were incubated (39 degrees C, 5% CO(2) in air) for 2 h in the following treatments: (i) 500 mu l of fertilization medium (FM); (ii) 250 mu l of FM with 0.25 ml of non-luteal ampullary uterine tube fluid (NLAUTF); (iii) 250 mu l of FM with 250 mu l of NLAUTF and 4 mu l of RCA-1 lectin; (iv) 250 mu l of FM with 250 mu l of NLAUTF, a rabbit polyclonal antibody (1:200) against purified bovine milk OPN, and RCA-1 lectin; (v) 500 mu l of FM and RCA-1 lectin. Following incubation, oocytes were washed, placed in FM with 2 mu g heparin, and incubated with 1 x 10(5) frozen-thawed spermatozoa per 10 oocytes. Oocytes used to assess sperm binding were stained with Hoescht 33342, and the number of sperm bound per zona pellucida counted. The remaining oocytes were fixed in acid alcohol, stained with 1% acetate-orcein and observed to determine the presence of pronuclei. More sperm bound to the zona pellucida (mean +/- SEM) when oocytes were incubated in treatment 3 (59.0 +/- 5.5) than in treatments 2 (46.4 +/- 5.6), 4 (18.1 +/- 5.4), 5 (33.4 +/- 5.6) or 1 (32.5 +/- 5.6). More oocytes were fertilized when incubated in treatment 3 (91% +/- 3.0) than in 2 (84% +/- 3.0), 4 (40% +/- 3.0), 5 (77% +/- 3.0) or 1 (76% +/- 3.0). As in previous studies, this study suggests that RCA-1 lectin enhances binding of UTF-derived OPN to bovine oocytes, resulting in increased sperm-egg binding and fertilization in vitro and a possible role in fertilization.

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Objective. This study investigated the prevalence of dental wear in 12-year-old adolescents using a modification of the tooth wear index (TWI). The modifications were proposed in order to fit with the World Health Organization standard, thus allowing application of the index in broad epidemiological surveys. Study design: An epidemiological cross-sectional survey was performed by trained, calibrated examiners, using a modified version of the TWI. Methods: Urban elementary schools were chosen because they provide a fair representation of the city`s population in terms of socio-economic status. The sample included 295 adolescents, selected randomly and systematically. Dental wear was assessed by calibrated examiners (kappa > 0.85), using a modified version of the TWI. This modified version includes a code for teeth restored due to wear, and another code for teeth that cannot be assessed. In addition, it does not differentiate the depth of dentine involvement. Proportions and confidence intervals were used to describe the prevalence of dental wear. Mann-Whitney test was used to detect differences in the degree of dental wear between mates and females. The level of statistical significance was set at 5%. Results: In total, 24,780 dental surfaces were evaluated. Among these surfaces, 73.10% did not present dental wear, 24.10% had incipient lesions, 2.46% had moderate lesions and 0.34% had been restored. No severe lesions were detected. Tooth wear was mainly seen on the occlusal/incisal surfaces (26.55%), involving enamel or enamel-dentine, but not the secondary dentine or pulp. The prevalence of dental wear was 26.90%. Considering the different teeth, wear was present in 53.22% of incisors, 50.51% of canines, 10.17% of premolars and 10.85% of molars. The prevalence of the different degrees of dental wear was similar in mates and females (P > 0.05). Conclusion: The modified TWI seems to bean effective toot for use in broad epidemiological surveys, due to easier calibration and high reproducibility rates. (C) 2008 The Royal Institute of Public Health. Published by Elsevier Ltd. All rights reserved.

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Objective: This study assessed the percentage of the amount of dentifrice loaded onto the toothbrush that is ingested by children, taking into account age, the amount of dentifrice used during toothbrushing, and the dentifrice flavor. Methods: The sample consisted of 155 children of both genders attending public kindergartens and schools in Bauru, Brazil, divided into 5 groups (n = 30-32) of children aged 2, 3, 4, 5 and 6 years old. The dentifrices used were Sorriso(TM) (1219 ppm F, peppermint-flavored) and Tandy(TM) (959 ppm F, tutti-frutti-flavored). The assessment of fluoride intake from dentifrices was carried out six times for each child, using 0.3, 0.6, and 1.2 g of each dentifrice, following a random, crossover distribution. Brushing was performed by the children or their parents/caregivers according to the home habits and under the observation of the examiner. Fluoride present in the expectorant and on toothbrush was analyzed with an ion-specific electrode after HMDS-facilitated diffusion. Fluoride ingestion was indirectly derived. Results were analyzed by 3-way repeated-measures anova and Tukey`s tests (P < 0.05) using the percent dentifrice ingested as response variable. Results: Age and percent dentifrice ingested for both dentifrices, and the three amounts used were inversely related (P < 0.0001). Percent dentifrice ingested was significantly higher after the use of Tandy(TM) under all conditions of the study when compared with Sorriso(TM) (P < 0.0001). Significant differences were observed when brushing with 0.3 g when compared with 1.2 g, for both dentifrices tested (P < 0.05). Conclusions: The results indicate that all variables tested must be considered in preventive measures aiming to reduce the amount of fluoride ingested by young children.

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Objective To evaluate the survival rate of dental implants placed in the cleft area Design Retrospective study Setting Hospital for Rehabilitation of Craniofacial Anomalies, Brazil Institutional Tertiary Healthcare Center Patients 120 patients who received dental implants in the grafted cleft area in the years 1999 to 2005 Interventions Clinical data were evaluated from the records of 120 patients according to the following criteria placement grafted, cleft area, and age at surgery, age at placement of dental implants, site and dimension of implants, interval between placement of implants and the last clinical follow-up, and interval between placement and removal or indication for removal of implants Main Outcome Measures Percentage of survival rate of implants Results Mean age at placement of the bone graft was 17 6 years and 21 years at placement of implants A total of 123 cleft areas received secondary bone graft and bone graft to install implants (regraft) The mean survival rate was 34 months since placement of the implant to the last clinical follow-up and 26 months since placement of the prosthesis Seven dental implants were removed The survival rate since placement to the last clinical follow-up was 94 3% Conclusion Rehabilitation of the cleft area with dental implants is a viable and secure alternative, with good prognosis